609.01Description.This
work consists of furnishing and constructing curb, combination curb and gutter,
medians, and traffic islands.This work
also consists of excavating, backfilling, furnishing and installing joint
materials, and disposing of surplus excavation and discarded materials
according to Item 203.

Furnish the best
quality of Berea or Amherst
gray sandstone, or sandstone of equal quality.

Furnish asphalt
concrete curb conforming to a 448 Type 1 intermediate course, designed for
medium traffic, using a PG 64‑22.Conform the asphalt concrete to the composition requirements with the
fine aggregate content set at the maximum allowed under this composition.Provided the Contractormeets the composition requirements, the
Contractor may add mineral filler conforming to 703.07.Add the mineral filler using a method approved by the Laboratory.

A.Cutting and Dressing.Ensure that 95 percent of all straight curb
pieces are at least 5 feet (1.5 m) long, with no pieces less than 42 inches
(1.1 m).The Contractormay use a piece as short as 30 inches (0.8 m)
for closure.For curves with a radius of
50 feet (15 m) or greater, the Contractor may use radially jointed straight
curb pieces between 36 and 42 inches (0.9 and 1.1 m) long.For curves and corners with a radius of less
than 50 feet (15 m), use pieces a minimum of 36 inches (0.9 m) long, and dress,
joint, and set pieces to the radii specified.For all curves and corners, use curb sections that are approximately
uniform in length.

Dress all curb to a straight edge on top and on
the exposed face and ends to a depth of at least 6 inches (150 mm) below the
gutter elevation.Dress the ends at
right angles to the face for straight curb and radially for curb on
curves.Do not allow slack or hollow
joints.Do not leave any projections
after dressing the ends of any curb section that exceed 1/8 inch (3 mm) from
the plane of the end of that section.Cut the edge next to the gutter to a 3-inch (75 mm) radius and dress the
top to a 1/4-inch (6 mm) bevel rising from the exposed face.Use a pitching tool on the edge at the back
to hand dress curb to the specified width.

B.Setting.Set the curb on a thoroughly compacted subgrade and with a 1 in 20
batter from the vertical backward from the gutter.If the subgrade consists of clay soils or
soils of a character that do not allow free drainage, place a minimum 3-inch
(75 mm) thick firm bed of porous material as a foundation for the curb.Use a heavy rammer to settle the curb into
place.Place and compact a minimum
4-inch (100 mm) wide porous backfill behind the curb to within
6 inches (150 mm) of the top.Bring
the balance of the backfill to the level of the top of the curb for a distance
of 2 feet (0.6 m) behind the curb with soil or other acceptable material.Thoroughly tamp the backing in layers not
exceeding 6 inches (150 mm) in thickness, loose measurement, with an approved
tamper or rammer.Perform as much of the
backfilling and tamping as is consistent with alignment of the curb at the time
the stone is first set.Set circular
curb in plastic concrete 6 inches (150 mm) thick as shown on the
plans.Extend concrete the width of the
curb plus 6 inches (150 mm) behind the curb, and bring concrete up behind the
curb to within 4 inches (100 mm) of the top.

C.Joints. Set curbs such that below the dressed portions
the space between ends of adjacent sections of curbing is not less than 1/8
inch (3 mm) at any point and not more than 4 inches (100 mm).Cushion the joints between the dressed
portions of adjacent sections of curbing with 1/8-inch (3 mm) thick expansion
joint material.Trim expansion joint
material flush with the curbing on all edges.

If placing sandstone curb after placing pavement,
fill remaining joints with dry sand to within 2 inches (50 mm) of the surface
of the pavement, and fill to the pavement surface with asphalt concrete.Take care in filling this joint so that no
asphalt concrete comes in contact with the exposed surface of the curb.

D.Reusing Existing as New Curb.If specifically allowed by the plans, and to the extent available, use
acceptable stone curb sections removed under Item 202 instead of furnishing new
stone curb.Use salvaged curb at
locations designated by the Engineer.Place all salvaged sections of curb
continuously without interspersing salvaged and new curb sections.Haul and store salvaged curb as
necessary.Cut, dress, set, and install
joints in salvaged curbs according to the requirements for new curbs.

A.Formsand Joints.Use approved steel forms for curbs.Securely brace and hold forms to the line and
grade shown on the plans.The Contractormay use approved flexible forms of steel or
wood to construct the radius of a circular curb 200 feet (60 m) or less.Immediately before placing concrete, clean
the inner surface of the forms, and coat this surface with a form release
agent.

Where curb and
combination curb and gutter is not constructed integral with, or tied to, the
base or pavement, construct 1/4-inch (6 mm) wide contraction joints at 10-foot
(3 m) intervals using steel separator plates, a grooving tool, or a saw
according to Item 451.For combination curb and gutter, construct
the joint to an average depth of 2 inches (50 mm) or more.For curb, construct the joint to an average
depth of one-fifth or more of the curb height.Where expansion joints occur in the abutting pavement, separate the
section being placed with 1-inch (25 mm) 705.03 preformed filler.

Where the curb is
integral with, or tied to, the base or pavement, construct the same type of
joints as used in the pavement.Space
joints identically with the joints in the base or pavement.

Leave curb forms in
place until their removal will not crack, shatter, or otherwise injure the concrete.Do not seal transverse joints in
cast-in-place concrete curb and combination curb and gutter.

If curbs are to later
serve as a support for a finishing machine in the
placing of a surface course, align supporting edges so that the distance
between the curbs is within 1/2 inch (13 mm) from that specified.

B.Placing.Place concrete in forms prepared as described
above, and vibrate the concrete to eliminate all voids.

Place concrete for curb
that is integral with the concrete base or pavement while the base or pavement
concrete is plastic.Where the presence
of the finishing equipment on the forms at the end of the day’s run prevents
completing the curb, install No. 5 (No. 16M) tie bars vertically in the
pavement at 1-foot (0.3 m) intervals and in a line 3 inches (75 mm) inside of
and parallel to the pavement edge.Install these tie bars to within 1 1/2 inches (38 mm) of the subgrade or
subbase and 2 inches (50 mm) above the concrete base or pavement surface.Water cure this horizontal construction joint
between the concrete base or pavement and the curb, or membrane cure the
concrete base or pavement and remove the membrane before placing the curb.Immediately before placing the concrete curb,
brush mortar (consisting of one part cement to two parts sand with enough water
to form a workable mortar) into the surface area of the hardened concrete
pavement or base where the curb is to be placed.Do not allow the mortar to dry before placing
the curb on top of it.

C.Slip-Form Placement.The Contractormay use a self-propelled machine to place
concrete curb or curb and gutter.Force
the concrete through a mold of the proper cross-section to obtain the proper
density and cross-section.If using a
track, set and secure the track on which the machine operates to the exact line
and grade given by the Engineer.Use concrete of a consistency that provides
the desired shape and remains as placed without slumping of the vertical faces.

D.Finishing.Without adding extra mortar, float the top of
the curb to thoroughly compact the concrete and produce a smooth and even
surface.Round the edges of the curb
using a tool specially designed for this purpose.Immediately after removing the forms, rub the
exposed face of the curb with a float to eliminate unnecessary tool marks.Provide a finished surface free of
irregularities and waves, and uniform in texture.

609.05AsphaltConcreteCurb.Use one of the following methods,
or other method approved by the Engineer, to furnish and place an
asphalt concrete curb of the required cross-section.

A.Method
A.After completing the surface
course, paint or spray only the area to be occupied by the asphalt concrete
curb with asphalt material conforming to 407.02.Apply the asphalt material at the rate of
0.15 gallon per square yard (0.7 L/m2).Place the curb with a hand-operated or
self-propelled machine consisting of a hopper and power-driven screw, which
forces the material through an extrusion tube.Force the material through a die attached to the end of the extrusion
tube to obtain the proper density and cross-section.

B.Method
B.As an independent operation
preceding the final rolling of the asphalt concrete surface course that the
curb is placed, place loose asphalt concrete of sufficient height and shape by
hand methods using suitable templates or by other means to produce the
specified cross-section.Compact the
loose asphalt concrete using a hand-operated mechanical vibrating tamper
equipped with a compacting shoe of such shape that will produce the specified
final cross-section dimensions of the curb.

A.Formsand Joints.Securely brace and hold
approved steel forms to the line and grade shown on the plans.The Contractormay use approved flexible forms of steel or
wood to construct a radius of 200 feet (60 m) or less.Immediately before placing concrete, clean
the inner surface of the forms, and coat this surface with a form release
agent.

Where medians and traffic islands are not anchored
to the pavement, construct contraction joints at 10-foot (3 m) intervals using
steel separator plates, a grooving tool, or saw according to Item 451. Construct
the joint using steel separator plates, a grooving tool, or saw according to Item 451.Construct the joint to a minimum depth of 2 inches (50 mm).

Where, as shown on the plans, the medians or traffic
islands are anchored to the pavement, construct the same type of joints in the
median or traffic island as used in the pavement.Space the joints identically with the joints
in the pavement.

Leave forms in place until their removal will not
crack, shatter, or otherwise injure the concrete.

B.Placing.Before placing a concrete median or traffic
island on subgrade, sprinkle the subgrade with water until thoroughly moistened
at times and in a manner directed by the Engineer.

Place the concrete in forms prepared as described
above, and vibrate the concrete to eliminate all voids.

C.Slip-Form
Placement.The Contractormay use a self-propelled machine to place
medians and traffic islands.Force the
concrete through a mold of the proper cross-section to obtain the proper
density and cross-section.If using a
track, set and secure the track on which the machine operates to the exact line
and grade given by the Engineer.Use concrete of a consistency that provides
the desired shape and remains as placed without slumping of the faces.

D.Finishing.Without adding extra mortar, finish the top
of the median or traffic island to a broom texture.Round the edges using a tool specially designed
for this purpose.Immediately after
removing the forms, rub the exposed faces with a float to eliminate unnecessary
tool marks.Provide a finished surface
free of irregularities and waves, and a uniform texture.

609.07Method of Measurement.The Department will measure Sandstone
Curb, Curb, Combination Curb and
Gutter, and AsphaltConcreteCurb by the number of feet (meters) complete
in place, measured along the front face of the curb section.

The Department will measure ConcreteTrafficIsland and Concrete Median by the number of
square yards (square meters) or the number of cubic yards (cubic meters)
complete in place.